/* grep.c - main driver file for grep.
Copyright (C) 1992 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
Written July 1992 by Mike Haertel. */
#include <errno.h>
#include <stdio.h>
#ifndef errno
extern int errno;
#endif
#ifdef STDC_HEADERS
#include <stdlib.h>
#else
#include <sys/types.h>
extern char *malloc(), *realloc();
extern void free();
#endif
#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
#include <string.h>
#ifdef NEED_MEMORY_H
#include <memory.h>
#endif
#else
#include <strings.h>
#ifdef __STDC__
extern void *memchr();
#else
extern char *memchr();
#endif
#define strrchr rindex
#endif
#ifdef HAVE_UNISTD_H
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#else
#define O_RDONLY 0
extern int open(), read(), close();
#endif
#include "getpagesize.h"
#include "grep.h"
#undef MAX
#define MAX(A,B) ((A) > (B) ? (A) : (B))
/* Provide missing ANSI features if necessary. */
#ifndef HAVE_STRERROR
extern int sys_nerr;
extern char *sys_errlist[];
#define strerror(E) ((E) < sys_nerr ? sys_errlist[(E)] : "bogus error number")
#endif
#ifndef HAVE_MEMCHR
#ifdef __STDC__
#define VOID void
#else
#define VOID char
#endif
VOID *
memchr(vp, c, n)
VOID *vp;
int c;
size_t n;
{
unsigned char *p;
for (p = (unsigned char *) vp; n--; ++p)
if (*p == c)
return (VOID *) p;
return 0;
}
#endif
/* Define flags declared in grep.h. */
char *matcher;
int match_icase;
int match_words;
int match_lines;
/* Functions we'll use to search. */
static void (*compile)();
static char *(*execute)();
/* For error messages. */
static char *prog;
static char *filename;
static int errseen;
/* Print a message and possibly an error string. Remember
that something awful happened. */
static void
error(mesg, errnum)
#ifdef __STDC__
const
#endif
char *mesg;
int errnum;
{
if (errnum)
fprintf(stderr, "%s: %s: %s\n", prog, mesg, strerror(errnum));
else
fprintf(stderr, "%s: %s\n", prog, mesg);
errseen = 1;
}
/* Like error(), but die horribly after printing. */
void
fatal(mesg, errnum)
#ifdef __STDC__
const
#endif
char *mesg;
int errnum;
{
error(mesg, errnum);
exit(2);
}
/* Interface to handle errors and fix library lossage. */
char *
xmalloc(size)
size_t size;
{
char *result;
result = malloc(size);
if (size && !result)
fatal("memory exhausted", 0);
return result;
}
/* Interface to handle errors and fix some library lossage. */
char *
xrealloc(ptr, size)
char *ptr;
size_t size;
{
char *result;
if (ptr)
result = realloc(ptr, size);
else
result = malloc(size);
if (size && !result)
fatal("memory exhausted", 0);
return result;
}
#if !defined(HAVE_VALLOC)
#define valloc malloc
#else
#ifdef __STDC__
extern void *valloc(size_t);
#else
extern char *valloc();
#endif
#endif
/* Hairy buffering mechanism for grep. The intent is to keep
all reads aligned on a page boundary and multiples of the
page size. */
static char *buffer; /* Base of buffer. */
static size_t bufsalloc; /* Allocated size of buffer save region. */
static size_t bufalloc; /* Total buffer size. */
static int bufdesc; /* File descriptor. */
static char *bufbeg; /* Beginning of user-visible stuff. */
static char *buflim; /* Limit of user-visible stuff. */
#if defined(HAVE_WORKING_MMAP)
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
static int bufmapped; /* True for ordinary files. */
static struct stat bufstat; /* From fstat(). */
static off_t bufoffset; /* What read() normally remembers. */
#endif
/* Reset the buffer for a new file. Initialize
on the first time through. */
void
reset(fd)
int fd;
{
static int initialized;
if (!initialized)
{
initialized = 1;
#ifndef BUFSALLOC
bufsalloc = MAX(8192, getpagesize());
#else
bufsalloc = BUFSALLOC;
#endif
bufalloc = 5 * bufsalloc;
/* The 1 byte of overflow is a kludge for dfaexec(), which
inserts a sentinel newline at the end of the buffer
being searched. There's gotta be a better way... */
buffer = valloc(bufalloc + 1);
if (!buffer)
fatal("memory exhausted", 0);
bufbeg = buffer;
buflim = buffer;
}
bufdesc = fd;
#if defined(HAVE_WORKING_MMAP)
if (fstat(fd, &bufstat) < 0 || !S_ISREG(bufstat.st_mode))
bufmapped = 0;
else
{
bufmapped = 1;
bufoffset = lseek(fd, 0, 1);
}
#endif
}
/* Read new stuff into the buffer, saving the specified
amount of old stuff. When we're done, 'bufbeg' points
to the beginning of the buffer contents, and 'buflim'
points just after the end. Return count of new stuff. */
static int
fillbuf(save)
size_t save;
{
char *nbuffer, *dp, *sp;
int cc;
#if defined(HAVE_WORKING_MMAP)
caddr_t maddr;
#endif
static int pagesize;
if (pagesize == 0 && (pagesize = getpagesize()) == 0)
abort();
if (save > bufsalloc)
{
while (save > bufsalloc)
bufsalloc *= 2;
bufalloc = 5 * bufsalloc;
nbuffer = valloc(bufalloc + 1);
if (!nbuffer)
fatal("memory exhausted", 0);
}
else
nbuffer = buffer;
sp = buflim - save;
dp = nbuffer + bufsalloc - save;
bufbeg = dp;
while (save--)
*dp++ = *sp++;
/* We may have allocated a new, larger buffer. Since
there is no portable vfree(), we just have to forget
about the old one. Sorry. */
buffer = nbuffer;
#if defined(HAVE_WORKING_MMAP)
if (bufmapped && bufoffset % pagesize == 0
&& bufstat.st_size - bufoffset >= bufalloc - bufsalloc)
{
maddr = buffer + bufsalloc;
maddr = mmap(maddr, bufalloc - bufsalloc, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_FIXED, bufdesc, bufoffset);
if (maddr == (caddr_t) -1)
{
fprintf(stderr, "%s: warning: %s: %s\n", filename,
strerror(errno));
goto tryread;
}
#if 0
/* You might thing this (or MADV_WILLNEED) would help,
but it doesn't, at least not on a Sun running 4.1.
In fact, it actually slows us down about 30%! */
madvise(maddr, bufalloc - bufsalloc, MADV_SEQUENTIAL);
#endif
cc = bufalloc - bufsalloc;
bufoffset += cc;
}
else
{
tryread:
/* We come here when we're not going to use mmap() any more.
Note that we need to synchronize the file offset the
first time through. */
if (bufmapped)
{
bufmapped = 0;
lseek(bufdesc, bufoffset, 0);
}
cc = read(bufdesc, buffer + bufsalloc, bufalloc - bufsalloc);
}
#else
cc = read(bufdesc, buffer + bufsalloc, bufalloc - bufsalloc);
#endif
if (cc > 0)
buflim = buffer + bufsalloc + cc;
else
buflim = buffer + bufsalloc;
return cc;
}
/* Flags controlling the style of output. */
static int out_quiet; /* Suppress all normal output. */
static int out_invert; /* Print nonmatching stuff. */
static int out_file; /* Print filenames. */
static int out_line; /* Print line numbers. */
static int out_byte; /* Print byte offsets. */
static int out_before; /* Lines of leading context. */
static int out_after; /* Lines of trailing context. */
/* Internal variables to keep track of byte count, context, etc. */
static size_t totalcc; /* Total character count before bufbeg. */
static char *lastnl; /* Pointer after last newline counted. */
static char *lastout; /* Pointer after last character output;
NULL if no character has been output
or if it's conceptually before bufbeg. */
static size_t totalnl; /* Total newline count before lastnl. */
static int pending; /* Pending lines of output. */
static void
nlscan(lim)
char *lim;
{
char *beg;
for (beg = lastnl; beg < lim; ++beg)
if (*beg == '\n')
++totalnl;
lastnl = beg;
}
static void
prline(beg, lim, sep)
char *beg;
char *lim;
char sep;
{
if (out_file)
printf("%s%c", filename, sep);
if (out_line)
{
nlscan(beg);
printf("%d%c", ++totalnl, sep);
lastnl = lim;
}
if (out_byte)
printf("%lu%c", totalcc + (beg - bufbeg), sep);
fwrite(beg, 1, lim - beg, stdout);
if (ferror(stdout))
error("writing output", errno);
lastout = lim;
}
/* Print pending lines of trailing context prior to LIM. */
static void
prpending(lim)
char *lim;
{
char *nl;
if (!lastout)
lastout = bufbeg;
while (pending > 0 && lastout < lim)
{
--pending;
if ((nl = memchr(lastout, '\n', lim - lastout)) != 0)
++nl;
else
nl = lim;
prline(lastout, nl, '-');
}
}
/* Print the lines between BEG and LIM. Deal with context crap.
If NLINESP is non-null, store a count of lines between BEG and LIM. */
static void
prtext(beg, lim, nlinesp)
char *beg;
char *lim;
int *nlinesp;
{
static int used; /* avoid printing "--" before any output */
char *bp, *p, *nl;
int i, n;
if (!out_quiet && pending > 0)
prpending(beg);
p = beg;
if (!out_quiet)
{
/* Deal with leading context crap. */
bp = lastout ? lastout : bufbeg;
for (i = 0; i < out_before; ++i)
if (p > bp)
do
--p;
while (p > bp && p[-1] != '\n');
/* We only print the "--" separator if our output is
discontiguous from the last output in the file. */
if ((out_before || out_after) && used && p != lastout)
puts("--");
while (p < beg)
{
nl = memchr(p, '\n', beg - p);
prline(p, nl + 1, '-');
p = nl + 1;
}
}
if (nlinesp)
{
/* Caller wants a line count. */
for (n = 0; p < lim; ++n)
{
if ((nl = memchr(p, '\n', lim - p)) != 0)
++nl;
else
nl = lim;
if (!out_quiet)
prline(p, nl, ':');
p = nl;
}
*nlinesp = n;
}
else
if (!out_quiet)
prline(beg, lim, ':');
pending = out_after;
used = 1;
}
/* Scan the specified portion of the buffer, matching lines (or
between matching lines if OUT_INVERT is true). Return a count of
lines printed. */
static int
grepbuf(beg, lim)
char *beg;
char *lim;
{
int nlines, n;
register char *p, *b;
char *endp;
nlines = 0;
p = beg;
while ((b = (*execute)(p, lim - p, &endp)) != 0)
{
/* Avoid matching the empty line at the end of the buffer. */
if (b == lim && ((b > beg && b[-1] == '\n') || b == beg))
break;
if (!out_invert)
{
prtext(b, endp, (int *) 0);
nlines += 1;
}
else if (p < b)
{
prtext(p, b, &n);
nlines += n;
}
p = endp;
}
if (out_invert && p < lim)
{
prtext(p, lim, &n);
nlines += n;
}
return nlines;
}
/* Search a given file. Return a count of lines printed. */
static int
grep(fd)
int fd;
{
int nlines, i;
size_t residue, save;
char *beg, *lim;
reset(fd);
totalcc = 0;
lastout = 0;
totalnl = 0;
pending = 0;
nlines = 0;
residue = 0;
save = 0;
for (;;)
{
if (fillbuf(save) < 0)
{
error(filename, errno);
return nlines;
}
lastnl = bufbeg;
if (lastout)
lastout = bufbeg;
if (buflim - bufbeg == save)
break;
beg = bufbeg + save - residue;
for (lim = buflim; lim > beg && lim[-1] != '\n'; --lim)
;
residue = buflim - lim;
if (beg < lim)
{
nlines += grepbuf(beg, lim);
if (pending)
prpending(lim);
}
i = 0;
beg = lim;
while (i < out_before && beg > bufbeg && beg != lastout)
{
++i;
do
--beg;
while (beg > bufbeg && beg[-1] != '\n');
}
if (beg != lastout)
lastout = 0;
save = residue + lim - beg;
totalcc += buflim - bufbeg - save;
if (out_line)
nlscan(beg);
}
if (residue)
{
nlines += grepbuf(bufbeg + save - residue, buflim);
if (pending)
prpending(buflim);
}
return nlines;
}
static char version[] = "GNU grep version 2.0";
#define USAGE \
"usage: %s [-[[AB] ]<num>] [-[CEFGVchilnqsvwx]] [-[ef]] <expr> [<files...>]\n"
static void
usage()
{
fprintf(stderr, USAGE, prog);
exit(2);
}
/* Go through the matchers vector and look for the specified matcher.
If we find it, install it in compile and execute, and return 1. */
int
setmatcher(name)
char *name;
{
int i;
for (i = 0; matchers[i].name; ++i)
if (strcmp(name, matchers[i].name) == 0)
{
compile = matchers[i].compile;
execute = matchers[i].execute;
return 1;
}
return 0;
}
int
main(argc, argv)
int argc;
char *argv[];
{
char *keys;
size_t keycc, oldcc, keyalloc;
int keyfound, count_matches, no_filenames, list_files, suppress_errors;
int opt, cc, desc, count, status;
FILE *fp;
extern char *optarg;
extern int optind;
prog = argv[0];
if (prog && strrchr(prog, '/'))
prog = strrchr(prog, '/') + 1;
keys = NULL;
keycc = 0;
keyfound = 0;
count_matches = 0;
no_filenames = 0;
list_files = 0;
suppress_errors = 0;
matcher = NULL;
while ((opt = getopt(argc, argv, "0123456789A:B:CEFGVX:bce:f:hiLlnqsvwxy"))
!= EOF)
switch (opt)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
out_before = 10 * out_before + opt - '0';
out_after = 10 * out_after + opt - '0';
break;
case 'A':
out_after = atoi(optarg);
if (out_after < 0)
usage();
break;
case 'B':
out_before = atoi(optarg);
if (out_before < 0)
usage();
break;
case 'C':
out_before = out_after = 2;
break;
case 'E':
if (matcher && strcmp(matcher, "egrep") != 0)
fatal("you may specify only one of -E, -F, or -G", 0);
matcher = "posix-egrep";
break;
case 'F':
if (matcher && strcmp(matcher, "fgrep") != 0)
fatal("you may specify only one of -E, -F, or -G", 0);;
matcher = "fgrep";
break;
case 'G':
if (matcher && strcmp(matcher, "grep") != 0)
fatal("you may specify only one of -E, -F, or -G", 0);
matcher = "grep";
break;
case 'V':
fprintf(stderr, "%s\n", version);
break;
case 'X':
if (matcher)
fatal("matcher already specified", 0);
matcher = optarg;
break;
case 'b':
out_byte = 1;
break;
case 'c':
out_quiet = 1;
count_matches = 1;
break;
case 'e':
cc = strlen(optarg);
keys = xrealloc(keys, keycc + cc + 1);
if (keyfound)
keys[keycc++] = '\n';
strcpy(&keys[keycc], optarg);
keycc += cc;
keyfound = 1;
break;
case 'f':
fp = strcmp(optarg, "-") != 0 ? fopen(optarg, "r") : stdin;
if (!fp)
fatal(optarg, errno);
for (keyalloc = 1; keyalloc <= keycc; keyalloc *= 2)
;
keys = xrealloc(keys, keyalloc);
oldcc = keycc;
if (keyfound)
keys[keycc++] = '\n';
while (!feof(fp)
&& (cc = fread(keys + keycc, 1, keyalloc - keycc, fp)) > 0)
{
keycc += cc;
if (keycc == keyalloc)
keys = xrealloc(keys, keyalloc *= 2);
}
if (fp != stdin)
fclose(fp);
/* Nuke the final newline to avoid matching a null string. */
if (keycc - oldcc > 0 && keys[keycc - 1] == '\n')
--keycc;
keyfound = 1;
break;
case 'h':
no_filenames = 1;
break;
case 'i':
case 'y': /* For old-timers . . . */
match_icase = 1;
break;
case 'L':
/* Like -l, except list files that don't contain matches.
Inspired by the same option in Hume's gre. */
out_quiet = 1;
list_files = -1;
break;
case 'l':
out_quiet = 1;
list_files = 1;
break;
case 'n':
out_line = 1;
break;
case 'q':
out_quiet = 1;
break;
case 's':
suppress_errors = 1;
break;
case 'v':
out_invert = 1;
break;
case 'w':
match_words = 1;
break;
case 'x':
match_lines = 1;
break;
default:
usage();
break;
}
if (!keyfound)
if (optind < argc)
{
keys = argv[optind++];
keycc = strlen(keys);
}
else
usage();
if (!matcher)
matcher = prog;
if (!setmatcher(matcher) && !setmatcher("default"))
abort();
(*compile)(keys, keycc);
if (argc - optind > 1 && !no_filenames)
out_file = 1;
status = 1;
if (optind < argc)
while (optind < argc)
{
desc = strcmp(argv[optind], "-") ? open(argv[optind], O_RDONLY) : 0;
if (desc < 0)
{
if (!suppress_errors)
error(argv[optind], errno);
}
else
{
filename = desc == 0 ? "(standard input)" : argv[optind];
count = grep(desc);
if (count_matches)
{
if (out_file)
printf("%s:", filename);
printf("%d\n", count);
}
if (count)
{
status = 0;
if (list_files == 1)
printf("%s\n", filename);
}
else if (list_files == -1)
printf("%s\n", filename);
}
if (desc != 0)
close(desc);
++optind;
}
else
{
filename = "(standard input)";
count = grep(0);
if (count_matches)
printf("%d\n", count);
if (count)
{
status = 0;
if (list_files == 1)
printf("(standard input)\n");
}
else if (list_files == -1)
printf("(standard input)\n");
}
exit(errseen ? 2 : status);
}
